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JavaScript

Posted by Asia Chan
Asia Chan
11,007 Points

jQuery/Javascript variable arrays, brackets [ ] or braces { }?

Hi! I'm at Andrew's Responsive Slider part for jQuery. At one point of the tutorial he said to create a new variable but he used braces { } instead of brackets [ ].

The code is as follows:

var options =  {navigationControl: 'false', animation: 'slide'};

From the earlier Javascript lessons I had learned to create arrays you need to use brackets [ ]. So what is the difference between braces { } and brackets [ ] in creating arrays? Which should I use during which occasions? Are the ones above called Associative Arrays, does that mean these arrays exist already and are just being referred to using braces { }?

As you can see, I'm pretty much the noobest noob at this lol. Thanks for taking time to answer!

Martin Teran
Martin Teran
Courses Plus Student 3,166 Points

This portion of "Intro to Programming" may help you out.

http://teamtreehouse.com/library/programming/introduction-to-programming/objects-and-arrays/objects

1 Answer

Philipp Antar
Philipp Antar
7,216 Points

Good question! Being a Rubyist, I was surprised to find that there is no actual Hash / Associative Array class in Javascript. What looks like an hash is acutally an Object. But it works just like a Hash:

var stuff = {'tree': 'plant', 'tiger': 'feline'}
stuff['tree']
--> "plant"
stuff['tiger']
--> "feline"

Here's some more info: http://www.quirksmode.org/js/associative.html